Interacting with the different endpoints is as simple as reading the API documentation. There are two main methods of the client to deal with - Client::get and Client::post - which take an endpoint as their first argument and the client parameters as the second.

Each request will return a PSR-7 response object, which you can read about on the Guzzle/PSR7 repo. The response object bodies have been decorated with a JsonSerializable interface to allow easier handling of the default API responses.